My choice would be based on my current need. How often are you getting punctures? How efficiently can you make repairs? Are you commuting to work where the delay from a flat repair results in lost wages or potential job loss? Then go with puncture resistant tires. Then add the flat resistant tubes if needed. If your tires are fairly new but prone to punctures, I would go with new puncture resistant tubes based solely on the cost. If I needed new tires and was primarily concerned about punctures I would get puncture resistant tires then add tubes if needed.